Field of the Invention
This invention relates to a technology for acquiring information relating to a target.
Description of the Background Art
In the related art, in a vehicle control system configured to follow up a preceding other vehicles and a vehicle control system configured to alleviate a collision with an obstacle, a radar apparatus configured to acquire information relating to a target in the periphery of a vehicle is used. The radar apparatus configured as described above transmits a transmitting wave, receives a reflected wave reflected from a target such as another vehicle, and acquires information such as a distance and a relative speed relating to the target on the basis of a received signal.
The radar apparatus transmits a transmitting wave, receives a reflected wave reflected from the target such as another vehicle, applies Fast Fourier Transform (FFT) on a beat signal on the basis of the received signal, and then extracts the beat signal exceeding a predetermined signal level as a peak signal. Subsequently, the radar apparatus acquires information such as the distance and the relative speed relating to the target on the basis of pair data obtained by pairing peak signals in respective periods of an up period and a down period in which a transmitting signal is modulated in frequency.
The radar apparatus then outputs the information such as the distance and the relative speed relating to the acquired target to a vehicle control apparatus, and the vehicle control apparatus performs vehicle control required based on the information relating to the target thereof.
However, when the vehicle is traveling in an environment in which the structure such as a truss bridge is present above, for example, a number of reflected waves are received from an upper object, so that erroneous pairing (erroneous pairing) may result. Consequently, correct information relating to the target cannot be acquired, and hence a detection performance is lowered, whereby erroneous vehicle control may occur.